JP2501678B2 - Raw fuel transportation control method - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention relates to a plurality of types of raw fuels.
The present invention relates to a transfer control method when transferring to a plurality of storage tanks in a factory by a plurality of belt conveyors.

[0002]

2. Description of the Related Art In steel mills and thermal power plants, an intermediate buffer (temporary storage) means called a yard is used to temporarily store raw fuels such as coal used for their operation. It has multiple storage tanks before each production process to make the quality and composition of raw fuel uniform. In a plurality of storage tanks, when a demand request is generated in the production process, a necessary amount is cut out and supplied to the production process, so that it is necessary to always store a certain amount of the required brand. Therefore, when the stock amount in the storage tank decreases, the necessary amount is cut out from the yarn and transferred to the storage tank by transferring to a conveyor device such as a belt conveyor.

Usually, in steel plants and thermal power plants, the scale of the plant is very large, the raw fuel brand and quantity are large, and a plurality of storage tanks are used as a buffer for temporary replenishment of the quantity, so that -It is important to improve the transport capacity from the storage tank to multiple storage tanks. For example, the raw fuel transportation system of a steel mill is
It consists of storage tanks in front of multiple yard, coke oven, blast furnace, sintering plant, etc., and multiple distribution equipment mainly consisting of belt conveyors for conveying raw fuel. is there.

(1) The stock level of each storage tank is maintained at a high level in order to achieve stable operation and cost reduction of production processes such as coke oven, blast furnace, and sintering.

(2) The work loss is reduced as much as possible to improve the efficiency of the raw fuel transportation work.

[0006] As an example, Fig. 4 shows a transfer system involved in the ironmaking coal preparation process. When the coal carrier 2 arrives at the base 1, the coal in the carrier 2 is unloaded by the unloader 3 and loaded on the stacker 4 in the coal yard 5, for example, 8 yard. If necessary, coal is cut out from the coal yard 5 by a reclaimer 6, for example, four reclaimers, and placed on a belt conveyor 8, for example, a belt conveyor selected from 24 systems. , Which is installed in each coke factory 11, for example, is conveyed to each of the 48 mixing tanks 7. In general, the important constraints of these transport processes are:

(A) Since each of the yarns 5 has a length of several hundred meters, the reclaimer 6 needs to move to a position where it can be cut each time the raw fuel mountain is switched, and the raw fuel mountain is cut. A loss time corresponding to the movement time of the reclaimer 6 will always occur at the timing of replacement. (b) A large number of belt conveyors 8 are provided in order to send raw fuel from a plurality of yard 5 to a plurality of storage tanks 7, but in general, it is independently conveyed from a certain yard 5 to a certain tank 7. Since the number of routes that can be formed is small, competition of the belt conveyor 8 easily occurs during the transfer work. (c) Recreation that can be moved at the same time due to restrictions on equipment, personnel, etc.
There is a limited number of machines 6, and preparation time is required to operate the reclaimers 6 other than those currently in operation. The most common method of efficiently operating in such an environment depends on experience and intuition. That is, according to the monitoring by the operator, the tank 7 inventory is gradually replenished and conveyed with the raw fuel below a certain value.
The inventory of the tank 5 and the tank 7 is manually managed.

[0008]

In the case of the conventional raw fuel transportation, when the transportation capacity per hour is much larger than the consumption per hour and the number of storage tanks to be filled is small, this is still a problem. However, in operating processes such as those found in steel mills and thermal power plants, the number of raw fuel brands and storage tanks is large, and the transfer capacity is not sufficient. Therefore, stock selection or reclaimer selection failure may result in inventory failure. Fluctuations or out-of-stocks occur, and we cannot hope to stabilize all tank inventories in the long run.

The present invention has a plurality of starting points and end points, has a plurality of transportation routes, as in the above-described raw fuel transportation system, and raw fuel transportation requests are simultaneously generated from multiple brands at any time, and Aiming to stabilize inventory for a long time by predicting future inventory changes, formulating a work plan with less work loss in a short time, and controlling according to the plan in a transport system in which transport equipment is likely to compete And

[0010]

The gist of the present invention is as follows: (1) Corresponding to a demand for transporting raw fuels of a plurality of brands, the raw fuels are transferred from a plurality of yards to a storage tank via a plurality of transport routes. In the process of carrying, the lower limit of the stock amount of each storage tank is set, and the transfer work candidates are set for each storage tank based on the forecasted stock transition of raw fuel in any time zone within the planned time zone . set the transportation task candidate with transport task candidate generating means
Then, the inventory quantity of the storage tank, the cut-out quantity, and the movement distance of the transportation equipment are used as the evaluation indexes for the transportation work candidates .
The transfer work is performed by the priority determination means using the G reasoning method.
The priority of the candidate is obtained, and among the transfer work candidates, the transfer work selecting means selects a combination of transfer works having high priority and capable of simultaneous transfer without any competition between transfer devices so that the transfer efficiency is maximized. selected, determined by the time determination means conveyance start and end times of the transport task candidates selected, pre
Decide the raw fuel transportation work between the start time and the end time,
For the transportation work after the end time, use the inventory calculation method.
It becomes impossible to incorporate the work within the planned period by calculating it and feeding it back to the priority determining means.
Alternatively, by recursively operating until all the transfer work candidates are exhausted, the transfer work schedule for the predetermined time period to be planned is determined, and the raw fuel is transferred according to the transfer work schedule. Characterized by
Raw fuel transfer control how, hierarchical fuzzy inference used in (2) above the priority determination means
The upper fuzzy inference method in the law
Membership for use in evaluation and subordinate fuzzy reasoning
The lower fuzzy inference method,
Use the defined membership function to meet the operating conditions.
The response was priority is determined for individual transport task candidates
The raw fuel transfer control method according to claim 1 ,
It is.

[0011]

[Function] By setting the lower limit of the stock amount of each storage tank and setting the transfer work candidate based on the stock fuel stock forecast during the planned time period, it becomes possible to grasp the density of the transfer work. In addition, the transfer work scheduling target can be limited.

For each of the transfer work candidates, the priority is obtained by comprehensively evaluating the stock amount of the storage tank, the cut-out amount, and the moving distance of the transfer equipment to determine the priority. As described above, the combination of the transfer work having the high priority and capable of simultaneous transfer without the competition of the transfer devices is selected, the transfer start time and the end time of the selected transfer work candidates are determined, and the inventory calculation, Feed back to priority determination,
By carrying out the recursive operation, the transfer work schedule in the planning time zone is determined, so that the transfer work is organized in order from the work having the highest priority as the transfer work candidate.

Further, according to one aspect of the present invention , the hierarchical fuzzy inference method is used for each transfer work candidate, with the stock amount of the storage tank, the cutout amount, and the moving distance of the transfer device as evaluation indexes.
The priority determining means automatically recognizes the operating conditions such as low or high inventory of the storage tank as a whole, and obtains the priority of the transfer work candidate adapted to the operating conditions.
It Specifically, this hierarchical fuzzy inference method is an evaluation of the overall low inventory of the storage amount , a high evaluation, etc. in the upper fuzzy inference method and the determination of the membership function used in the lower fuzzy inference method. However, in the lower fuzzy reasoning method, the membership function determined in the upper level can be used to determine the priority level adapted to the operating condition for each individual transfer work candidate (hereinafter, the above-mentioned upper level). ,under
A fuzzy inference method called a fuzzy inference method set in a hierarchy of ranks ).

As described above, by organizing the transfer work in order from the work having the highest priority among the transfer work candidates, the transfer work schedule adapted to the operating conditions is determined, and complicated calculation is not required.

Among the transfer work candidates, the transfer efficiency can be improved by selecting a combination of transfer works that have a high priority and can be simultaneously transferred without competition of transfer devices so that the transfer efficiency is maximized. .

In the mechanism for obtaining the priority, by taking into consideration the moving distance of the reclaimer, the schedule of the transfer work with less loss time can be planned.

As a whole, the present invention can accumulate the knowledge experience of the operator's transfer control method, which has dealt with this problem for many years, into priorities by the hierarchical fuzzy inference method, and transfers it in a short time by a simple calculation. A highly efficient transportation plan can be obtained.

[0018]

EXAMPLES Details of examples of the present invention will now be described with reference to FIGS.
It will be described based on the following. FIG. 2 shows the configuration of the transfer work planning means according to the present invention.

The first thing to do is to set the transfer work candidates of the brand to be transferred by the transfer work candidate generating means 12. In order to keep the inventory of the mixing tank of the coke oven at a high level, it is necessary to manage the lower limit value. Generally, the time when the tank inventory level reaches the lower limit is set as the entry time, and the work schedule is determined by predicting the inventory transition for each tank and determining the entry time. Can be uniquely planned. However, as a practical matter, this work plan is extremely unlikely to cause equipment competition between transport works, and is unlikely to be a work plan with little loss time.
rare. Therefore, by providing a transfer work candidate at the time when the lower limit value is reached and using the time when the lower limit value is reached as a guide, by allowing the actual transfer start time to be earlier or later than the time when the lower limit value is reached, Relax the conditions.

The second thing to do is to obtain the priority of the transfer work candidate by the priority determining means 13. Here, the reason for obtaining the priority is to make it possible to easily determine the order of the transfer work by expressing a plurality of evaluation indexes such as the stock amount of the storage tank, the cut-out amount, and the moving distance of the transfer device with one index called the priority. In point. The concept of the priority of the transfer work candidate can be divided into the following two depending on the operating conditions such as the stock of the storage tank being high or low as a whole.

(1) When the stock of storage tanks is high as a whole, the evaluation of tank stock is emphasized, and the priority of the transfer work candidate to the tank with low stock is set high, so that the tank stock is almost the same. if there is,
If the priority of the transfer work candidate to the storage tank with a large amount of cutout is high and the tank inventory and the cutout amount are similar, the
Consider the distance traveled. The order of consideration for the indicators is as follows. Tank inventory ＞ Cutout amount ＞ Reclaimer movement distance This is because the inventory of the storage tanks has a margin, so we aim to stabilize the inventory of each storage tank at a high level.

(2) When the stock of the storage tank is low as a whole, importance is attached to the reclaimer movement distance, and the priority is given to the work candidate of the brand which has a short reclaimer movement distance and can be transported. However, if the reclaimer movement distance is similar, the priority of the transfer work candidate to the storage tank with a small inventory quantity is set high, and if the reclaimer movement distance and tank inventory are similar, the cutout amount is Consider. The order of consideration for the indicators is as follows. Reclaimer movement distance ＞ Tank inventory ＞ Cutout amount This is because the inventory of the storage tank is not sufficient, so we aim to recover the inventory of the storage tank by minimizing the loss time and improving the transportation efficiency.

As described above, it is possible to set the priority level adapted to the operating condition by the two rules. These rules are derived from the knowledge and experience of the operators who have dealt with this problem for many years, and the operators operate by using each rule flexibly. In actual operation, however, it is difficult to accurately grasp the entire target range and use the rules in a short time because there are many brands of raw fuel and storage tanks and the transport capacity is not sufficient. The rule was applied according to the appropriate condition.

Therefore, the state is determined more accurately from the entire target range and the above rule is applied to improve the planning accuracy. In addition, these rules have a wide range of application, and there are application areas that overlap each other. In these areas, it is necessary to use both rules in combination, so the application range of these two rules is With a definite number,
The upper fuzzy reasoning method and its results are used without case classification.
Found a lower fuzzy reasoning method to use in a hierarchy
Then, I tried to realize it. FIG. 1 shows an explanatory diagram of the hierarchical fuzzy inference method. First, the upper fuzzy reasoning is used to evaluate whether the storage tank inventory is low or high, and the lower fuzzy reasoning method is used to determine the tank stock cutout amount and the membership function of the reclaimer movement distance. . Next, in the lower fuzzy inference, the priority of the transfer work candidate is individually obtained by using the membership function determined in the upper fuzzy inference. As a result, it becomes possible to determine the priority level adapted to the operating conditions.

Thirdly, among the transfer work candidates, the combination of the transfer works having the high priority and capable of simultaneous transfer without the competition of the transfer devices is transferred so that the transfer efficiency is maximized. This is to be selected by the work selecting means 14.
Here, since the work is searched in order from the highest priority,
It is possible to select the optimal combination of transfer operations with a small number of searches.

Fourthly, the time determining means 15 determines the transfer start time and the end time of the selected transfer work. The details are shown in the explanatory diagram for determining the transport start time and end time in FIG. The transport start time should be as early as possible because reducing the lost time as much as possible during the planning period enables work plans with high transportation efficiency. Therefore, the start time of the planned period or the end time of the starting transfer work is set as the transfer start time. In addition, the end time is the time when the upper limit is reached earliest in the selected transportation work.

Fifthly, what should be done is to feed back to the second priority determining means 13, calculate the inventory by the inventory calculating means 16, and perform the priority calculating 13. It will operate recursively until it becomes impossible to incorporate or there are no transfer work candidates.

[0028]

According to the present invention, as compared with the conventional method, the stock level of the tank can be improved and the loss time in the transfer operation can be shortened. The most characteristic feature of the present invention is that an optimal solution can be obtained in a short time and no complicated calculation is required. Of course, because equipment-dependent rules are used, some process modifications may be required for different processes. However, many of the problems we face always have some of the rules pointed out in this invention. In the present invention, since the incorporation and addition of these rules can be reflected in the priority, the device can be modified and applied.

[Brief description of drawings]

1 is a block diagram illustrating a process of hierarchical fuzzy inference to practice the present invention.

FIG. 2 is a block diagram showing functions for implementing the present invention.

FIG. 3 is a graph showing a relationship between time and tank stock quantity, which is determined according to an embodiment of the present invention.

FIG. 4 is a block diagram showing a raw fuel transportation system in a pig iron coal preparation step, which is one of the symmetrical operations of the present invention.

[Explanation of symbols]

1: Bus 2: Coal carrier 3: Unloader 4: Stacker 5: Coal yard 6: Reclaimer 7: Mixing tank 8: Belt conveyor 9: Coal crusher 10: Coal blender 11: Co- Furnace 12: transfer work candidate generation means 13: priority determination means 14: transfer work selection means 15: transfer work start time and end time determination means 16: inventory calculation means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsuhiro Nakanishi 5-3 Tokai-cho, Tokai-shi Nippon Steel Corporation Nagoya Steel Works (72) Inventor Hiroyuki Iida 5-3 Tokai-cho, Tokai-shi Nippon Steel Co., Ltd. Nagoya Works (72) Inventor Yuji Kato 5-3 Tokai-cho, Tokai City Nippon Steel Information and Communication Systems Co., Ltd. Chubu Branch (56) Reference JP-A-4-89709 (JP , A) JP-A-4-89708 (JP, A)

Claims (2)

(57) [Claims] 1. A stock of each storage tank in a process of transferring raw fuel from a plurality of yards to a storage tank via a plurality of transfer routes in response to a plurality of brands of raw fuel transfer requests. Set a lower limit of quantity and set any time within the planning time zone
Transferring the transfer work candidates to each storage tank using the transfer work candidate generation means based on the forecasted changes in the inventory of raw fuel in the belt
Candidates are set, and the stock amount in the storage tank, the cut amount, and the movement distance of the transportation device are used as evaluation indexes for the transportation candidate.
By the priority determination means using the hierarchical fuzzy inference method,
The priority of the transfer work candidate is obtained, and in the transfer work candidate,
By the transport work selection means, the transport efficiency is maximized.
Selecting a combination of the transfer works having high priority and capable of simultaneous transfer without contention of the transfer devices, and determining the transfer start time and end time of the selected transfer work candidates by the time determination means , Decide the raw fuel transportation work between the start time and end time
The inventory calculation means also calculates the transportation work after the end time and feeds it to the priority determination means.
It is impossible to incorporate the work back within the planning period
Until it becomes available or there are no transfer work candidates , the transfer work schedule for the predetermined scheduled time zone is determined by operating recursively, and the transfer work schedule is determined. According to the method, the raw fuel is conveyed, and the raw fuel conveyance control method. 2. A hierarchical fuzzy used in the priority determining means.
-In the inference method, the upper fuzzy inference method
For use in inventory valuation and subordinate fuzzy reasoning
Determine the membership function, and in the lower fuzzy reasoning method,
Using the membership function determined by
Determine the priority that suits the situation for individual transfer work candidates.
2. The raw fuel transfer control according to claim 1, wherein
Method.